Devolo G3-PLC Modem 500k, Руководство пользователя

Страница: 37 / 42

Configuration
devolo G3-PLC Modem 500k
37
4.7.1Scenarios and configuration
���
Extending a serial connection
If two devices are connected over RS232 or a master is connected with many slaves
over RS485, this connection can be extended by adding two G3-PLC modems connect-
ed over PLC:
In the case of an RS485 connection, additional devices may be connected to the master:
In such cases, the enquiries from the master and the responses from the local slaves are
transmitted to the remote devices over PLC, as they cannot be differentiated from one
another. As a result, both the local and the remote slaves always see all the data, as is
the case with a purely local connection.
Both G3-PLC modems can be configured with identical parameters. The serial param-
eters are set to the parameters used previously for the direct connection. If one of the
devices is a PAN coordinator, the roles can be selected automatically for piping over
IP. Then, this device becomes the IP server and the other becomes the IP client device.
The port must be identical. The buffer size and timeout values have to be selected
based on the requirements of the protocol.
If there are two PAN clients, one device must assume the role of the server and the oth-
er, the role of the client. In this case, the IP address of the server must be configured in
the client. This is possible only if a third device is available to operate as a coordinator
and the PAN clients are able to communicate with each other directly.
���
Serial connection over IP
In this scenario, there is a master that must have a LAN connection but does not require
a serial interface. Only communication with the slaves is transmitted over the serial in-
terface(s).
The master must also have software that can send the data on a TCP/IP connection or
over UDP so that they can be sent to the slaves as needed. This does not require a spe-
cial protocol. Each byte received by the G3-PLC modem over IP is sent with the con-
figured parameters over the serial interface and each character received by the modem
Fig. 6
Fig. 7